Current trends in surgery have been focused heavily on operating techniques which strive to be as non-invasive as possible. Small incisions are made in the patient, and specialized instruments, with small cutting heads and viewing devices are inserted into the patient to perform the necessary surgery. The problem is however that, if the tissue being operated on is to be sutured, it is very difficult to perform the suturing through the small incision which has been made in the patient. Accordingly, there is a need for a suture fastener and a suturing instrument which can be used in such minimally invasive surgery.